Method of and apparatus for pumping wells



May 1, 134. c. J. COBERLY Er AL METHOD OF AND APPARATUS FOR PUMPINGWELLS Filed Dec. 19, 1932 i 3 Sheets-Sheet l H4 AAS.

' y 1934- c. .1. COBERLY ET AL 1,957,320

METHOD OF AND APPARATUS FOR PUMPING WELLS Filed Dec. 19. 1932 3Sheets-Sheet 2 Fga Cmesrvcs 605524,. Faea M Haze/s,-

y 1, 1934s C.'J. COBERLY ET AL 1,957,320

METHOD OF AND APPARATUS FOR PUMPING WELLS Filed Dec. 19, 1952 'sSheets-Sheet s vm n 427 I l 1 I I I I L ii 1% ,4 I! L Patented'May 1934f .951.320 METHOD OF AND- mmrrus lion. rmmna warms "am... i. Coberiy andFord w. Harris, m Angeles, Calif., assignors to Kobe, Ina, HuntingtonPark, Calif., a corporation of California Application December 19, 1932,Serial No. 647,925

7 Claims.

The invention is particularly applicable to wells which are pumped byfluid pressure pumps, al.- though applicable. under certain conditons toother pumping systems. It is particularly applicable to the pumping ofdeep oil wells by means of fluid pressure pumps.

The standard method of pumping an oil well at the present time is bymeans of a pump placed at or near the bottom of the well, this pumpbeing 10 actuated through pump rods which are connected to this pump andwhich extend up inside the tubing of the well, being actuated, bysuitable pumping'mechanism placed in the derrick above the surface ofthe ground. Such pumps while l5 quite satisfactory for wells of moderatedepth, have proved quite unsatisfactory in very deep wells, 1. e., wellshaving a depth of 5,000 feet or more. In these deep wells the stretchingof the pump rods and the tubing is excessive, thus cutting down theefiective stroke of the pump, and in.

these deep wells thefactor of safety in the pump rods is necessarilysmall due to the weight of the rods and the column of fluid which it isnecessary to sustain thereon.

To overcome these difficulties various inventors have devisedfluid-operated pumps in which oil under pressure is used as a motivepower for a fluid motor placed just above and connected to the pumpproper which is situatednear the bot- 'tom of the well. Suchfluid-operated pumps may 40 in thederrlck above the surface of theground,

a this actuating pump being driven by .a suitable source of power andbeing used to supply 011 under pressure to an oil supply pipe leading tothe fluid motor in the well.

It is diflicult to determine exactly how much oil a well will produce,and although the productive capacity of the well does not ordinarilysuddenly change, there is usually a slow decrease in productive capacitydue to the exhaustion of they oil sands around the well. Since the fluidmotor is linked to the actuating pump at the surface of the ground bymeans of-a column of oil, the capacity of the apparatus to pump oil fromthe well is governed by the speed of the actuating pump. The speed ofthe actuating pump can,

of course, be regulated by a suitable speed regulator applied to thedriving means-therefor, but since these pumps operate for long periodswithout an attendant, frequent changes in the speed of the actuatingpump may be necessary if the well is to be kept pumped down (that is,with its fluid at its lowest depth at which the pump in the well withoperate), and the'operation of the pump in the well at low eflicienciesis to. be avoided, since if the pump is operated at a higher capacitythan the well will produce, it will eventually exhaust the oil in thewell and start to pump gas. Itis highly desirable that the well be keptpumped down.ii the well is to produce a maximum amount of 011, since bykeeping the fluid levelof the oil in the well very low, there is nowhich the pump will operate at a high efliciency.

. Further objects and advantages will be made evident hereinafter.

Referring to the drawings, which are for illusv trative purposes only: I

Fig. 1 shows in diagrammatic form the appa-' ratus required when ourinvention is applied to a fluid-operated pump applied to an oil well.

Fig. 2 is a diagram of the electrical connections 'by which the pump iscontrolled.

, Fig. 3 is a diagram showing an alternate method of connection.

Fig. 4'is a diagram showing another alternate method of connection.

Fig. 5 is a general assembly of the apparatus shown in Fig. 4. a

In the form of the invention illustrated, an oil well is shown having abore 11 which extends down from the surface of the ground 12 any desireddistance. It is practical by using our invention to eificiently andpositively pump wells which are 6,000 feet deep or deeper. Our inventioncan, of course, be applied to shallow wells and is quite eflicient whenso applied, butit has a peculiar utility when applied to very deep wellsin which the present methods of pumping are not satisfactory.

The bore 11 of the well may be casedwith a steel casing which may beperforated at the bottom in accordance with standard practice. Thiscasing is not sliown since it forms no part of our present invention.

Suspended in the well is tubing 13. This tubing may be either of therotary or reciprocating type.

In the apparatus shown, the oil is passed through the fluid motor 16 toactuate same, and

after the pressure of the oil has'been reduced by the operation of themotor 16, it passes through openings 19 into a space 20 between thepressure pipe 15 and the interior of the'tubing 13.

The pump 18 shown in the drawings draws oil through an opening 21 whichcommunicates with the space 22 in the well outside the tubing 13 anddelivers this oil through openings 23 into the space 20. A standingvalve 48 may be provided in the opening 21 for holding the oil in thespace 20 when the apparatus is not operating. Oil from the space 20flows through the delivery pipe 14 to tankage or through an auxiliarytank 25 from which it is conducted througha pipe 26 to suitable storage.T

The motor 16 operates the pump 18 at a deflnite rate which is determinedby the rate at which oil is delivered to the motor 16through the pres:sure pipe 15. Oil .is delivered to the pressure pipe 15 through a pipe2'7 which is connected to the pressure side of an actuating pump 28.This actuating 'pump may be of any desired form,

many pumps being now available which may be used for this service. Thepump shown is therefore diagrammatic and consists of a pump cylinder 30having a plunger 31 which is connected through a connecting rod 32 witha cross-head 33. The cross-head 33 is reciprocated through a connectingrod 34 driven by a crank 35 carried on a shaft 36. The shaft 36 is,driven by any suitable means such as a pulley 37, a belt 38, and apulley 39 from a shaft 40 of an electric motor 41. A pressure valve45and an exhaust valve 46-are provided, the pressure valve 45 preventingoil from passing fromthe pipe 2'7 into the interior of the cylinder 30,and the exhaust valve 46 being so placed as to prevent oilfrom passingbackwardly from the cylinder 30 into a' suction pipe 4'7 which draws oilfrom the tank 25.

As the piston 28 moves upwardly, it draws oil through the suction pipe4'7 past the valve 46, tilling the cylinder, the valve 45 beingin itsclosed position. 0n the down stroke of the piston 31, the valve 46seats, and oil from the cylinder passes the valve 45 into the pipe 2'7.The actuating pump therefore periodically delivers oil under pressure tothe pipe. 27. In actual practice the actuating pump 28 will be providedwith several cylinders so that substantially continuous delivery of oilto the pipe 2'7 is provided for.

All of the above apparatus is old in the art and no claim is madetheretoexcept in combination with certain methods of and apparatus forcontrolling its operation. In practice the various parts are made ofsufficient size so that'by their combined operation oil may be pumpedfrom the well at a' considerably faster rate than the well willnaturally produce oil. In other words, if the apparatus were allowed torun continuously, it would pump the fluid in the .well'down to a pointwhere only gas would be drawn in through the opening 21. For example, ina'well which will produce a maximum of 100 barrels a day, the capacityof the apparatus previously described operating continuously should bein excess of 100 barrels a day and might be as high as 200 barrels perday.

It is highly desirable that the oil in the well be maintained at as lowan average level as possible so that there will be no back pressure onthe oil sands surrounding the well due to av column of oil standing inthe well. This condition can be assured by usingcur invention in whichone form apparatus is shown diagrammatically, and stand ard apparatus isavailable on the market which will perform the functions thereof. Thisstandard apparatus may have a different form from that shown. Thecontactor 61 is shown in the form of a solenoid having a core 71, thiscore being pulled upwardly as the solenoid '70 is actuated. The core '71lifts a member '72, which bridges main contacts '73 when the core '71 isin its lower position. A member 74 is also attached to the core 71 whichconnects setting contacts '75 when the core '71 is pulled up. A member'76 attached to the core '71 connects locking contacts '77 when the coreis pulled up. .The contactor 61 is preferably of the instantaneous type,that is, it is not provided with any means for retarding itsoperation.The instantaneous underload relay 62 consists of a solenoid which pullsa core 81 upwardly when the solenoid is energized, the core 81 beingattached to a member 82 which closes underload contacts 83 when the coreis down. A stop 84 is provided for limiting the upward movement of themember 82, and the relay 62 is so constructed that the position of thestop 84 may be regulated, or the weight of the moving parts may beregulated so that the core 81 will drop whenever the current in thesolenoid 80 falls below a predetermined value. This value may beapproximately eighty per cent or less of the current taken by the motorwhen pumping at full capacity.

The time reclosing relay consists of'a solenoid 85 which pulls upwardlyon a core 86 and which carries a member 87 which closes reclosingcontacts 88 when the core is down. A dash-pot 89 or other adjustableretarding mechanism is provided for preventing the core 86 from movingupwardly for a definite time after the solenoid 85 is energized. Thistime may be assumed to be ten minutes, although it may be a longer orshorter period, if desired. In other words, the circuit through thecontacts 88 is opened about ten minutes after the solenoid 85 isenergized.-

The time limit relay 64 consists of a solenoid 90 which pulls upwardlyon a core 91 when the solenoid is energized, causing a member 92 toclose time relay contacts 93. A dash-pot 94 is also attached to thecore, this dash-pot providing a time element which may be about tenseconds. In other words, the circuit through the contacts 93'is closedby the member 92 about ten seconds after the solenoid 90 is energized. Astarting switch 95 is provided which may be closed or opened manually tostart or stop the pump.

7 drops, closing a circuit through the contacts 83." The relay 64 havingpreviously operated the circuit is also closed through the contacts 93.-This Current is supplied from asuitable source of supply through wires100 and 101. .7 H

The wire 100 isconnected to one terminal of the armature 50 and thefield 51 of the motor. and is also connected to'a control wire 102leading to one terminal of the solenoid '70 and to one of the settingcontacts '75. The-other terminals. of the armature 50 and held 51 areconnected through a wire 103 with one side of the solenoid of theinstantaneous underload relay 62, the other side of this solenoid 80being connected through a wire 104 with one of-the contacts '73. Theother side of the solenoid '70 is connected through a wire 105 with oneof the locking contacts '77 and with one of the contacts 93. .The othercontact 93 is connected through a wire 106 with one of the contacts 83,the other contact 83 being connected to a wire 107 which connects withone of the contacts '77 andone of the contacts 88. The other side ofthesolenoid 90 is connected to the wire 104. The wire101 is connected tothe starter 95, the other'side of which is connected.

to one of the contacts '73, to one side or the solenoid and 0 one of thecontacts 88. The other side of the solenoid 85 is connected to one oithe contacts '75. i

The method of operation is as follows:

Prior to starting operations, all the parts are in the position shown inFig. 2, and no current flows in any circuit shown therein. The operatorstarts operations by closing the starter 95 which energizes the motorthrough the contacts '73 and the solenoid 80 of the instantaneousoverload re-- lay. This starts the motor which operates the actuatingpump 28 and pumps oil under pressure through thepipe 2'7to the fluidmotor 16. Ordinarily, \the starting current of the motor is considerablymore than its normal full load current, and this heavy starting currentcauses the solenoid 80 of the instantaneous relay 62 to pull the core 81upwardly, thus opening the circuit through the underload contacts 83.

t For the purpose of preventing premature operation of the other controlparts prior to the time the motor builds up its full load we use thetime limit relay 64. It will be noted that the circuit through thecontacts 93 is normally opened and is not closed until ten seconds afterthe solenoid is energized. This time element of ten seconds isarbitrarily chosen for purposes of description, and under certainconditions of operation it may be advisable to make it longer orshorter. The solenoid 90 is energized whenever the motor 41 isenergized, since the solenoid 90 is in parallelwith the motor.

The time limit chosen for the relay 64 must be such that the motor 41can build up its full load before circuit is closed through the contacts93. As long as this circuit is open the position of the member 82 of therelay 62 is oi no importance, since the contacts '93 and the contacts 83are in series. As soon as the motor has built up its full load currentthe solenoid 80 will have opened thecircuit through the. contacts 83 andwill be held in its upper position as long as the motor 41 draws itsfull load current.

The motor now operates the actuating pump until thelwell pumps down",that is, until the level of fluid in the well falls below the'intakeopening 21 or the pump 18. As soon as this occurs, the pump 18 ceases totake oil and the current on thrmotor falls due to a decrease in the loadthereon. j

The current in the solenoid 80 (which is in series with the motor 41)falls and the core 81 circuit is fed through the wire 101 and. thecontacts 83 and 93 to the solenoid '70 of the contactor' 61 andcompleted through the wire 102 to the wire 100.

This causes the core '71 to bepulled upwardly,

breaking the main circuit at the contacts '73 through the solenoid 80and the motor 41' and opening the circuit through the solenoid 90. The

motor then stops and pumping ceases.

' Due to the member '76 closing a circuit through 4 in its open positionuntil its solenoid circuit is opened at the contacts 88. i

As the core '71 moves into its upperposition it closes a circuit throughthe setting contact '75,

this circuit including the solenoid 85 of the reclosing relay 63. Thisrelay operatesto open the circuit through the contacts 88 when adefinite time has elapsed after the solenoid 85 is energized. We mayassume this time to be ten minutes, although this time may be longer orshorter, depending upon conditions. Whatever the time may be, it remainsdefinite and constant unless the relay 63 is readjusted by the operator.when this definite time interval has elapsed, the circuit through-thecontacts 88 and the solenoid '70 is opened at the contacts 88 andcurrent being'cut ofl from the solenoid '70, the core '71 drops. i

This restores the apparatus to the condition shown irnFig. 2, exceptthat the core 86 of the relay 63 is in its upper position. The relay 63is so constructed that the core 86 drops immediately after the circuitis cut oil through the solenoid 85. I

The closing of the main circuit through the contacts '73 causes themotor to start, and the time limit relay 64 to be energized, and thecycle to be repeated. p I

In Fig. 3 we show an alternate method of control. In this figure weshowa motor 201' fed with a three-phase alternating current from the wires202 through a three-pole main contactor 203 having an operating coil204. The contactor shown is of the gravity release type; that is, themoving element drops intothe position shown in Fig. 3 whenever thecircuit of the coil 204 is opened. A time limit relay 205 is provided?this relay having a coil 206 and being adapted to close a circuitbetween stationary contacts 207 a definite time after the coil 206 isenergized. This time may, for example, be ten minutes. The relay 205 ispreferably of the quick return type; that is, it drops freely to thelowerposition, shown is opened, although requiring ten minutes to risefrom its inactive position shown in Fig. 3 to its closed position inwhich the contacts 207 are connected together by the movable element208.

The relay shown is, of course, entirely diagrammatic and in practice weuse a relay of a motordriven type which, however, accomplishes the sameresult. I

We also provide a change-over relay 210 having a coil 211 and two pairsof stationary c0ntacts 212 and 213. The relay 210 is also of the gravityrelease type, the moving parts dropping intothe position shown in Fig. 3whenever current is cut off from the coil 211. 'The relay 210 may beprovided with two movable bridging 212, the bridging member 215 beingheld against v the contacts 213.

When the coil 211 is energized and the relay is moved to closedposition, the collar 218 strikes against the bridging member 215,lifting it away from the contacts 213. Before the circuit is broken atthe contacts 213 the spring 216 will have forced the bridging member 214into contact with the contacts 212 so that during thetransition fromopen'to closed position the circuit between the contacts 212 and thecircuit between the contacts 213 are both closed for, a short interval.

The purpose of this arrangement is to prevent either circuit beingbroken until after the other is established, this purpose being, ofcourse, capable of accomplishment by various devices which might besubstituted for the relay 210.

We also provide a pressure switch'220 which in the form shown-consistsof a block 221 having a cylindrical opening therein, the lower end ofthis opening being connected through a pipe 222 with the pipe 27 ofFig. 1. A piston223 slides freely in the opening, being held in theposition shown in Fig. 3 by a compressionspring 224 which pressesagainst a stationary abutment 225. A piston rod 226 carries abridgingmember 228 which is insulated from the rod 226 and which in its lowerposition as shown in Fig. 3 closes a circuit between stationary contacts227. ,The purpose or the pressure switch is to open the circuit betweenthe contacts 227 whenever the pressure on the bottom of the piston 223rises above a certain value fixed by the spring 224, and it will beobvious that any 01 many well-known types of pressure switches could besubstituted therefor.

We also provide a manually operable switch 230 having a movable arm 231which is shown in its oil? position indicated at 233. One end of thisarm may be'moved into its -automatic position in contact with a contact232, as shown in dotted lines, Fig. 3, or into its hand position incontact and the other terminal is connected through a a contact 212.

wire 302 with. the contact 234, through a wire 303 with a contact, 207,and through a wire 304 with The other contact 212 is connected through awire 309 withthe contact 232 and the other contact 2071s connectedthrough a wire 315 with the contact 232. The arm 231 is permanentlyconnected through a wire 305 with the wire 202-'2.

One terminal of the coil 206 is connected through a wire 306- with thecontact 232, and the other terminal of the coil 206 is connected througha wire 307 with a contact 213, the other contact 213 being connectedthrough a wire 308 with the wire 202-1.

One terminal of the coil 211 is connected through a wire 310 withthewire 202-1, and through a wire 311 with a contact 227. The otherterminal of the coil 211 is connected through a wire 312 with oneterminal of the resistance 240, and through a wire 313 with a. contact227. The other terminal of the resistance 240 is connected through a'wire 314 with the contact 232.

t will be obvious from the above description and Fig. 3 that the coil204 of the main contactor 203 maybe energized either'by moving the arm231 of the manually operable switch 230 to the contact 232, or by a.closure of the circuit between the contacts 207 of the time relay 205,or by a closure of the circuit between the contacts 212 205 isenergized, however, when the movable arm 231 is on the contact 232 andthe circuit is completed between the contacts 213, as shown ini intheoiT position and-all of the apparatus is in the position it assumesprior to starting operations. When it is desired to start. the-pump inoperation, the moving arm 231 is moved into contact with the contact 234and the coil 204 of the main contactor 203 is energized, closing themain contactor circuit and starting the motor. This motor will then rununtil the arm 231 is moved 011 the contact 234. a v

The starting of the motor causes the pump 28 to build up a pressure inthe pipe 27, which pressure is communicated to'the piston 223, .thispressure being sufl'icient to move the piston 223 upwardly against thepressure of the spring 224 and to open the circuit at the contacts 222'.If after the pump is started it is desired to put it in condition'tooperate automatically, the arm 231 is moved to the automatic position incon- .tact' with the contact 232. The coil 206 is thereby energized andthe time relay 205 starts to move. upward slowly. It will be rememberedthat it takes ten minutes for this relay to complete its operation.

At the time the arm 231 is moved to the automatic position, currentflows through the wire 314, resistance 240, the coil 211, and the wire310 so that the coil 211 is energized, it being understood that thecircuit between the contacts 227 is then open due to the pump being inoperation and oil pressure being exerted on the piston 223.

The moving of the arm 231 from the contact 234 opens the circuit to thecoil 204, and the main contactor 203 opens the circuit to the motor,which would eventually stop if the main contactor 203 were notimmediately closed. Owing to the fact that there is considerable inertiain'the oil moving in the pipe27, although the current is interruptedfrom the motor, the pressure on the piston 223 does not immediately falland before this-pressure can, fall sufficiently to close the circuitbetween the contacts 227, the changeover relay, which is of the quickacting type,

operates, first closing the circuit between the contacts 212,- and thenopening the circuit between the contacts 213. As soon as the circuitbetween the contacts 212 is closed, the main contactor 203 Zisimmediately thrown in so that current is again supplied to the motor andthe apparatus continues to operate. It will be noted that by theoperation of the change-over relay 210, the circuit through the coil 206has been opened at the contacts 213 and the time relay 205 quicklyreturns to its initial positionas shown in Fig. 3. v

The pump then operates until such a-time as the well is pumped down; inother words. until there is no oil to be lifted irom the well, at whichtime the oil pressure in the pipe 2'? falls due to the fact that it hasno work to do except to overcome the frictional head. The spring 224 isof such strength that Just before the well is entirely pumped down, thespring 224 iorces the piston 223 downwardly and closes the circuitbetween the contacts 227. This short-circuits the coil 211 and thechange-over relay 210 drops, thus disconnecting the circuit through thecoil 204 of the main contactor at the contacts 212. The main contactor203 then opens and the pump stops.. At the same time the change-overrelay 210 closes the circuit to the coil 206 of the time 1 relay'and thetime limit relay starts to operate.

After a definite time interval, which, for illustration, we haveselected as ten minutes, during which the pump. is not operating, thetime relay completes its operation and closes the circuit between thecontacts 207. This energizes the coil 204 and the main centactor 203closes, thus again starting the motor. Since oil has collected in thewell during the time the apparatus is shut down, the pump immediatelybuilds up suiiicient pressure to open the circuit between the contacts227, which again energizes the coil 211 of the changeover relay 210. Therelay 210 then closes the circuit to the coil 204 by completing thecircuit between the contacts 212 and opens the circuit through the coil206 by opening the circuit between the contacts 213. The closing of thecircuit through the coil 204 insures the main con-= tactor 203 remainingclosed after the time limit relay. 205-drops due to the circuit throughthe coil 206 having been opened at the contacts 213.

The apparatus then repeats the cycle. The pump continues to operate fora sufiicient period to pump down the well,'at which time the maincontactor opens and the motor shuts down. After an interval of say tenminutes the pump is again started.

In Fig. 4 we show another method of control. In this ,figure we show thepump 28, the pressure pipe 2'? leading from the pump down to the well tosupply a motive fluid to the motor 16, the easing 13, and the pipe 14bringing fluid from the casing head. We then provide a closed tank 401,the

pipe 14 being connected in gas-tight relationship in the top thereof.We-also provide a pipe 402 passing in gas-tight relationship through thetop of the tank401 and leading from the bottom a Wm d chiick any reverseflow from th Pipe 403 to the pipe 405, a I if Connected into the tank401 near the top thereof is a pipe 410 which is connected to aconstricted orifice 411, the other end of which is connected into a pipe414. The pipe 414 is in turn com nected to a pressure regulating valve412. A pipe 413 leads from the regulating valve tostorage.

. We may use as the pressure regulating valve 412 any of the well-knownvalves of this type which have the characteristic of remaining closeduntil the pressure in the pipe 414 is in excess of the pressure in thepipe 413. This difference in pressure is commonly known as the operatingpressure of the valve. The valve 412 is set so that it requires anoperating pressureslightly in excess of the available pressure in thepipe 405.

In this method of connection we use the apparatus shown in Fig. 3 exceptthat we substitute for the pressure switch 220 a diaphragm switch 420,substituting for the'contacts 227 contacts 421, these contacts beingconnected to the wires i 311 and 313 of the diagram shown in Fig. 3.

We may use as a diaphragm switch 420 any 0! several well-known forms,that shown consisting of a diaphragm 422 carried in a casing 423, thespace inside the casing to the left of the diaphragm 422 being connectedto the pipe 410 by a small pipe 424, and the space inside the casing 423to the right of the diaphragm 422 being connected to the pipe 414 by asmall pipe 425. A compression spring 426, the tension of which may beadjusted by a hand-wheel 427, is provided, this spring tending to forcethe diaphragm to the left as shown in Fig. 4. An operating rod 428carries a bridging member 429 which closes the circuit between thecontacts 421 at all times unless there is an excess of pressure in thepipe 424 over the pressure in. the pipe 425. Whenever this, excesspressure reaches a certain value, which is determined by adjusting the.tension of the spring 426, the diaphragm 422 is moved to the right andthe bridging member 429 is pulled away from the contacts 421, thusopening the circuit therebetween.

The method of operation of the apparatus,

when the method'oi. control shown in Fig. 4 is If it is desired tooperate the pump continuously; the arm 231 is thrown into, the handposition in which it makes contact with the contact 234, thusenergizingthe coil 204 of the'main contactor 203, and starting the pump inoperation. The pump creates a suction on the pipe 47 and oil underpressure from the pipe 405 will flow freely through the check valve '404and the pipe 403. The pump then delivers-oil to the well 1 until suchtime as all of the piping, including the casing 13, is filled with oiland return oil starts 'to be delivered through the pipe 14 to the tank401.- As soon as oil starts to fill the tank 401 pressure starts tobuild up therein and as soon as the pressure in the tank 401 is inexcess oi the -140 pressure in the pipe 405, the check valve 406 closesand no more oil is delivered to' the system,

the pump 28 taking 'oil through the P1118 402 from the bottom ofv thetank and recirculating it.

Since the pump 16 in the bottom of the well is 145 to open the'regulating valve 4 so that oil'may 1 9 be delivered through the pipes410, 411, 414, and 413 to storage. Whenever the pressure built up in theconstricted pipe 411 exceeds the pressure of the spring 426, thispressure moves the diaphragm 422 and opens the circuit between thecontacts 421. These contacts are connected to the coil 211 in exactlythe same manner as the contacts 22'? shown in Fig. 3 and as long as thebridging member 429 is in contact with the contacts 421, the coil 211 isshort-circuited and inoperative. As soon as the bridging member 429 ispulled away from the contacts 421, the coil 211 is in a condition to beenergized. In other words, the pump operates with the member 231 in thehand position until oil starts to be delivered to storage through thepipe 413. If now the arm 231 is moved to the contact 232 or automaticposition, the coil 206 of the time relay is,

of course, energized, but since this relay moves very slowly, thecontacts 207 are not immediately closed. The coil 211 of the change-overrelay 210 is, however, energized and circuit is immediately made to thecoil 204 of the main contactor through the contacts 212. If the arm 231is moved slowly the main contactor may drop out during the transitionperiod of the movable arm 231 from the contact 234 to the contact232,but as soon as it.reaches the contact 232 the main contactor isimmediately thrown'in and the pumping continues.

It will be understood that due to the inertia of the oil, the diaphragmswitch 420 will not have time to act during this transition period. Thepump therefore continues to operate and the moving oil in theconstriction 411 holds the diaphragm switch 420 in its open position.

As soon as the well pumps down or the flow of oil in the constriction411 ceases for any rea-' son, there will be no difference in pressure inthe pipes 424 and 425 and the spring 426 pushes the bridging member 429into the position shown in Fig. 4, thus closing the circuit between thecontacts 421. This short-circuits the coil 211 of the change-over relay210 and the bridging members 214 and 215 drop into the position shown inFig. 3, thus opening the circuit of thecoil 204 of the main contactor203 at the contacts 212 and closing the circuit of the coil 206 of thetime relay 205 at the contacts 213. The motor stops due to the maincontactor opening and the time relay starts to operate.

During the time the time relay is operating, which we have assumed to beten minutes, the pump will be shut down and no oil will flow. At theexpiration of this ten minute period the bridging member 208 of the timerelay will close the circuit between the contacts 207, thus energizingthe coil 204 of the main contactor 203 and closing the main circuit andstarting the motor. Due to the factthat the pump has been shut down forten minutes, it may require some time for the flow of oil to bereestablished through the constriction 411. Whatever this time maybe,'the apparatus will'continue to operate without any change in theposition of any part thereof until sufficient pressure is .establishedbetween the pipes 424 and 425 due, to the constriction 411 to operatethe diaphragm switch.

Ordinarily the period required to reestablish the flow of oil throughthe constriction 411 will be short. The pump will, however, operateuntil this flow of oil is reestablished and if necessary during thisperiod it will pump oil from the pipe 405. Assoon as oil starts to flowthrough the constriction 411 at a sufllcient rate to operate thediaphragm switch 420, the circuit between the contacts 421 isopened,thus operating the change-over switch 210 and opening the circuit to thecoil 206 of the time relay 205 and simultaneously closing the'circuitthrough the coil 204 of the main contactor. The main contactor is, ofcourse, closedat the time this occurs, the purpose of closing thecircuit to the contacts 212 being to insure the main contactor remainingclosed as the time relay drops to its open position.

The pump will now continue to operate with the change-over switch closeduntil such a time as oil ceases to flow through the constriction 411 insulficient amount to hold the diaphragm switch open. If the well pumpsdown or for any other reason the flow in the constriction 411 ceases,the diaphragm switch will close and the circuit to the coil 211 of thechange-over switch 210 will beinterrupted and this switch will drop.This will open the circuit to the coil 204 of the main contactor 203,thus shutting down the motor, and will start the time relay in operationso that the motor will be started again in ten minutes.

It will be noted that the above-described method of control has severaladvantages. the first place, the pump will operate, taking oil from thepipe 405 if necessary, until such a time as an adequate flow of oil isestablished in the constriction 411. The pump will further continue tooperate as long as this flow in the constriction 411 continues at a ratesufilcient to hold the diaphragm switch open. As soon as the flow ceasesthe pump is shut down and remains shut down for a period of say tenminutes. At the end of this time the pump again starts and then pumpsfor a sufiicient period to reestablish the flow regardless ofconditions.

A very convenient arrangement of the apparatus is that shown in Fig. 5in which a pressure regulating switch 420 is used as above described andin which the pressure regulating valve 412 is dispensed with and thepipe 414 is carried up and delivers oil into the top of a tank 500, thepipe 405 in this case being connected to the bottom of this tank and anoverflow pipe 501 being provided for taking excess oil from the top ofthe tank 500. The tank 500 should be of sufiicient size to fill thepiping of the entire system in the event the pump is shut down for anyreason and the piping is allowed to drain.

It may take a few minutes or a much longer time for the cycle ofoperation to be completed. As soon as the fluid in the well is pumpeddown the motor stops and remains stopped for a deflnite time (assumedfor illustrative purposes to be ten minutes). During the time the pumpis inactive (that is, for ten minutes) fluid enters the well fromthesurrounding sands. At the end of said period of ten minutes the pumpis again started and operates for whatever period is necessary to againpump the well down. When this condition .is reached the pump is againshut down for ten minutes.

It will be seen that the pumping cycle is divided into two periods; thatis, a definite and constant time period assumed to be ten minutes, andan indefinite time period which depends on how much-fluid runs into thewell during the entire 1 i-so 1,957,320.. Y; cycle as long as fluidflows into the well at the rate of one hundred barrels per day. 1

As the fluid is exhausted in the sands surrounddecrease. The pumpingintervals will then become shorter. For example, when the rate of fiowfalls 'to twenty barrels per day the wellwill pump two and one-halfminutes and remain shut down. for ten minutes. Or, in the event the rateof flow of oil into the well increases for any reason, 'the pumpingintervals will automatically become longer. For example, with a pumphaving a capacity of two hundred barrels a day and adjusted for a tenminute idle period, if the oil flows into the well at the rate of onehundred fifty barrels per day, the pump will operate thirty minutes andremain shut down for ten minutes.

It will be seen that the pumping period will vary to suit the capacityof the well without the necessity for any change or adjustment in theapparatus, the shut-down period remaining constant.

Among the advantages the following:

(a) The same apparatus may be used in all wells having a productivecapacity less than the capacity of. the apparatus. In other words, anapparatus having a capacity of two hundred barrels per day will pumpall.wells having a lesser capacity.

(b) The apparatus when operating will run atits fullrated capacity andat high efliciency.

.(c) The apparatus will keep the well pumped down so that. at no timewillthere be in the well more oil than will run in during the deflniteperiod for which the relay 63 is set.

(d) A constant speed motor 41 maybe used to operate the actuating pumpand no resistance'-- or'other speed regulator is needed in connectiontherewith.

(e) When the apparatus is once installed it will operate over a longperiod without varying the adjustments thereof even though the amount offluid running into the well may vary considerably. a

While We have described in the above description three methods ofinsuring the desired result of intermittent pumping, it should beunderstood that we do not wish to limit ourselves to anyone of thesethree methods; In other words, our invention'broadly contemplatespumping the well for a suiflcient period to pump it down, then allowingit to stand for a definite time interval; during which the well refillsitself, and then repeating the cycle. While we illustrate inFig. 1 amethod in which we accomplish" this result, by

utilizing the current flowing to the motor as an actuating force fordetermining the timelg-i ior shut-down, we show ini ig. 3 a method of'utiliaing the pressure in the pipe 27' for determining the time ofshutdown, and we show in Fig. 4 a method of utilizing the rate of flowof the oil in the pipe 410 for determining the time oi shutdown, werecognize that there may be other methods by, which this result. may beaccom-,

'plished and we do not wish to limit ourselves to any of the illustratedmethods, all or which come within the scope of the following claims.What-' ever system of control-is used, the general result is the samewhen the apparatus is 'operating automatically. The motor operates thepump far a suflicient period to pump down the fluid in the? well. T

of this arrangement are We claim as our invention:

1. ,A method of pumping a fluid from a well,

which comprises: pumping said fluid from said certain predeterminedvalue due to the exhaustion of fluid in said well; allowing'the fluid toflow into the well, without pumping for a deflnite time interval;resuming said pumping at the end of said time interval; and continuouslyrepeating the cycle.

2. In a well pumping outfit adapted torepcatedly pump a wellsulfliciently toreduce the fluid level ther'einto a definite low pointregardless of variations in rate of flow of fluid into said well, thecombination of: a.pump adapted to reduce said level when in operationlbyremoving fluid from said well at a rate greater than the maximum'rate offlow of fluid into said well; means for'preventing the fluid in saidwell from being pumped below said low point by stopping said val haselapsed after each'stopping of said pump.

3. In a well, pumping outfit adapted to repeatedly pump a wellsufdciently to reduce the fluid level therein to a deflmte low pointregardless of variations in rate of flow of fluid into said well.

the combination of a pump adapted to reducesaid level when in operationby removing fluid from said well at a rate greater than the maxlmum rateof flow of fluid into said well; means for preventing the fluid in saidwell from being pumped below said low point by stopping said pumpautomatically whenever said fluid is pumped down to said low point;means adapted to re-start said pump after each stoppage thereof by againsupplying power thereto; and'a definite time element means for insuringthat the pump shall be inactive for a period of deflnite duration byactuating said re-starting means whenever said periodhas elapsed afterany stoppage,

pumped below said low/pointv by stopping said pump automaticallywhenever the rateof flow "of the fluid delivered from said pump-fallsbelow a predetermined minimum; and means for insuring that the pump willeventually remove all the fluid which flows into said well by startingsaid pump whenever. adeiinite time interval has elapsed after eachstopping or said pump.

5. In a, well pumpingoutflt adapted to repeatedly pump a" wellsufficiently to reduce the fluid level therein to a definite low pointregardless of variations in rate-orflow o! fluiddnto said well, thecombination of: 1a pump'adapted to reduce thefluid delivered from saidpump falls below apredetermined minimum; means adapted to restart saidpump after each stoppage thereof by again supplying power thereto; and adefinite time element means for insuring that the pump shall be inactivefor a period of definite duration by actuating said re-starting meanswhenever said period has elapsed after anystoppage of the pump. r L

6. In a well pumping outfit adapted to repeatedly pump a wellsuificiently to reduce the fluid level therein to a definite low pointregardless of variations in rate of flow offluid into said well,

the combination of: a pump adapted to reduce termined minimum wheneversaid fluid is pumped said level when in operation by removing fluid fromsaid well at a rate greater than the maximum rate of flow of-fluid intosaid well; means for stopping said pumpby discontinuing the apesplication of power thereto; means for actuating said stopping meanswhenever the power'required to drive the-pump falls below apredetermined minimum whenever said fluid is pumped down to said lowpoint; and means for insuring that the pump will eventually remove allthe fluid which flows into said well by starting said pump whenever adefinite time interval has elapsed after each stopping of said pump.

7. In a well pumping outfit adapted to repeatedly pump a wellsufficiently to reduce the fluid level therein to a definite low pointregardless of variations in rate of flow of fluid into said well, thecombination of: a pump adapted to reduce said level when ,in operationby removing fluid stopping said pump by'discontinuing the application ofpower thereto; means for actuating said stopping means whenever thepower re; quired to drive the pump falls below a prededown to said lowpoint; means adapted to restart said pump after each stoppage thereof byagain supplying power thereto; and a definite time element means forinsuring that the pump shall be inactive for a period of definiteduration by actuating said 're-starting means whenever said period haselapsed after any stoppage of the pump. 77

CLARENCE J. COBERLY. FORD W. HARRIS.

